Version $A$

$7.$ You kick a block which has a mass of $3\mathrm{.}15$ kg $.$ Three seconds later it is sliding is sliding down a ramp that is $=36\mathrm{.}9$ above the horizontal. The coefficient of kinetic friction, ${}_k,$ between the block and the ramp is $0\mathrm{.}425.$ In this situation, what is the magnitude of the acceleration of the block?

a$.,9\mathrm{.}22\frac{m}{s^2}.$

$($b$.)7\mathrm{.}84\frac{m}{s^2}.$

$($c$.)2\mathrm{.}55\frac{m}{s^2}.$

d$.5\mathrm{.}88\frac{m}{s^2}.$

$a=\frac{24\mathrm{.}7}{3\mathrm{.}15}=7\mathrm{.}84$

e$.,9\mathrm{.}80\frac{m}{s^2}.$