An electrician has 4.1 meters of wire. how many strips of 7/10 meter long can he cut?

Which matrix multiplication is possible?

I’ve been trying all day to figure this puzzle out. i need the work for it aswell. it is a factoring polynomials tarsia. the image is below.

Which equation can be used to measure the density of water in a spherical water tank? let w represent the number of water particles within the region.