I think its C. but im not really sure. Well i hope im correct or at least helped u :D
In 5 days, = 175 pages
so, in 1 day = 175/5 Pages
Now, In 2 days, it would be: 175/5 * 2 = 35 * 2 = 70
So, your final answer is 70
Hope this helps!
5000-850=
$4150 left to raise
$4150/83 students=
$50/student