Lake Mead, the reservoir above Hoover Dam, has a surface area of approximately 640 km2. The top 1 meter of water in the lake weighs about 6.3 x 1012 N. The dam holds that top layer of water 220 m above the river below, What is the potential energy of the top 1 m of water in Lake Mead. Group of answer choices

140800 j

2156 j

1.38 x 10^15 j

14367.3 j

The boy of mass 30 kg is at r1= 2 meters from the fulcrum. of the girl is 45 kg, at what r2 must she sit so that they are balanced ?

10 newton object is placed 3 meters from the fulcrum. at what distance on the other side would you need to place a 15 newton object to balance the lever? show your work!

Two students, each riding bicycles, start from the same apartment building and ride to the same building on campus, but each takes a different route. the first student rides 1100 m due east and then turns due north and travels another 1430 m before arriving at the destination. the second student heads due north for 1930 m and then turns and heads directly toward the destination. at the turning point, how far is the second student from the destination?