If you drop a 2.2kg ball from the top of a 42m high building, how fast will it be going just before it hits the ground? Round to the nearest tenth and include the appropriate unit

Two red blood cells each have a mass of 9.0 multiply. gif 10-14 kg and carry a negative charge spread uniformly over their surfaces. the repulsion arising from the excess charge prevents the cells from clumping together. one cell carries −2.50 pc of charge and the other −3.10 pc, and each cell can be modeled as a sphere 7.5 μm in diameter. (a) what speed would they need when very far away from each other to get close enough to just touch? assume that there is no viscous drag from any of the surrounding liquid. answer is: 321 m/s how do i find this (b) what is the maximum acceleration of the cells in part (a)? answer is: 1.38e+10 m/s2 how did they find this answer

Let v1, v2, w be three linearly independent vectors in r 3 . that is, they do not all lie on the same plane. for each of the following (infinite) set of vectors, carefully sketch it in r 3 , and determine whether or not it is a vector space (i. e., a subspace of r 3 ). explain your reasoning

If 21.2 kcals of energy is released by this reaction, how many kj does the reaction release? (1 cal 4.184 j)