A particle of mass $2 \mathrm{~kg}$ moves with an initial velocity of $v=(4 \hat{i}+4 \hat{j}) \mathrm{m} / \mathrm{s}$. A constant force of $F=-20 \hat{j} \mathrm{~N}$ is
applied on the particle. Initially, the particle was at (0,
0). The $x$ -coordinate of the particle when its $y$ -coordinate again becomes zero is given by
a. $1.2 \mathrm{~m}$
b. $4.8 \mathrm{~m}$
c. $6.0 \mathrm{~m}$
d. $3.2 \mathrm{~m}$