How many neutrons does element x have it it’s atomic number is 32 and it’s mass number is 81?

Describe different biomes. what are some adaptations that organisms (plants or animals) must have to live in each biome?

Asled is being held at rest on a slope that makes an angle θ with the horizontal. after the sled is released, it slidesa distance d1 down the slope and then covers the distance d2 alongthe horizontal terrain before stopping. find the coefficient ofkinetic friction μk between the sled and the ground, assumingthat it is constant throughout the trip. find the coefficient of kinetic frictionμk. express your answer in terms of someor all of the variables d1, d2, and θ.

Dentist's chairs are examples of hydraulic lift systems. if the chair weighs 1,600 n and rests on a piston with a cross-sectional area of 1,440 cm2, what force must be applied to the small piston, which has a cross-sectional area of 72 cm2, to lift the chair?