I think of the i and j to be x and y coordinates
a) distance travelled in one second = sqr(5^2+8^2) = sqr(89) =(around) 9.43 ms^-1
b) P = (2+5t)i + (1+8t)j ------- just thinking components
c) looking at i-axis, 1 second to move 5 right, so 8/5 seconds to move 8 right
8/5 sec = 1.6 sec
d) P(1.6) = 10i + 13.8j
7j + aj = 13.8j -------- a is distance travelled by player
aj = 6.8j
a=6.8
v = d/t = 6.8/1.6 = 4.25 ms^-1
e) friction
Might need checking, but it looks right to me