Solve (2u+v)*(u-5v) where the vectors u and v are orthogonal and unit vectors in Rn

How many degrees does the hour hand move from 3: 00 to 5: 30?

Suppose that 15 inches of wire cost 60 cents. at the same rate, how much (in cents) will 12 inches of wire cost

Whoever gets this right gets the ! the half life of a soul smelling substance is 4 years. if you have 8 oz of this strange substance, how much of it will you have after 20 years? show work.