Diving goggles are not allowed in the swimming pool because they are designed for use in deep water and can obstruct peripheral vision, increasing the risk of collisions with other swimmers. Additionally, diving goggles are not necessary for swimming laps or recreational swimming in a pool with clear water. The use of diving goggles in a swimming pool can also create a safety hazard if the wearer dives into shallow water thinking it is deeper than it actually is. **

Using a diving mask instead of swimming goggles can provide a wider field of vision and better visibility underwater. Diving masks are designed to create a watertight seal around the eyes and nose, preventing water from entering. They also typically have a nose pocket for equalizing pressure while diving. However, diving masks may be bulkier and less streamlined than swimming goggles, which could affect comfort and performance while swimming laps. **

Lower Saxony is called Lower Saxony because it is located in the northern part of Germany and historically was part of the region known as Saxony. The name "Lower" distinguishes it from the neighboring region of Upper Saxony, which is located further south. The term "Saxony" itself comes from the Saxons, a Germanic tribe that inhabited the area during the early Middle Ages. Therefore, Lower Saxony is named after its historical and geographical connection to the region of Saxony. **

To lower the pH level of a green pool, you can add muriatic acid or sodium bisulfate to the water. Follow the manufacturer's instructions for the correct dosage based on the size of your pool. It's important to test the pH level regularly and adjust as needed until it reaches the optimal range of 7.2-7.6. Additionally, you can improve circulation and filtration in the pool to help distribute the chemicals evenly and aid in balancing the pH level. **

Grasshoppers belong to the order Orthoptera, which also includes crickets and katydids. Within the order Orthoptera, grasshoppers are classified in the suborder Caelifera. Further classification places grasshoppers in the family Acrididae, which is the largest family within the suborder Caelifera. This family includes a wide variety of grasshopper species found all over the world. **

Poplars belong to the genus Populus, which is part of the family Salicaceae. Within the genus Populus, there are several species of poplars, including Populus nigra (black poplar), Populus deltoides (eastern cottonwood), and Populus tremuloides (quaking aspen). These different species have their own unique characteristics and are classified further into various subspecies and varieties based on specific traits and geographical distribution. **

Frogs belong to the class Amphibia, which is further divided into three orders: Anura (frogs and toads), Caudata (salamanders), and Gymnophiona (caecilians). Within the order Anura, frogs are classified into various families, genera, and species based on their physical characteristics and genetic relationships. This hierarchical classification system helps scientists organize and study the diverse group of frogs found around the world. **

Owls belong to the order Strigiformes and are further classified into two families: Strigidae (typical owls) and Tytonidae (barn owls). These families are then divided into various genera and species based on their physical characteristics and behaviors. **