Apply: conservation of momentum

A person applies a $20\text{N}$‍ force for $2\text{seconds}$‍ to a shopping cart with an initial momentum of $-60\text{kg}\cdot {\displaystyle \frac{\text{m}}{\text{s}}}$‍ to slow it down. What is the change in momentum of the shopping cart?
Your answer should have one significant figure.

$\text{kg}\cdot {\displaystyle \frac{\text{m}}{\text{s}}}$‍