5*4*6=120
4+(6+9)=19
675+9=75
this is the answer you can try it to see if it works
$42 what you do is take $1400 times .03 which equals 3 percent and you get 42.
s(t) = 65+24sin(0.3t)
where t is measured in hours since 5:00
a.m
3-hour period from 7:00 a.m. to 10:00 am
5 am to 7 am = 2 hours
5 am to 10 am = 5 hours
To find the number of tons we take integral of 2 to 5 of s(t)
∫ 2 to 5 s(t) = ∫ 2 to 5 (65+24sin(0.3t))
∫65+24sin(0.3t) dt = 65t - 80 cos(0.3t) + c
Now we plug in the bounds 2 and 5
∫ 2 to 5 (65+24sin(0.3t)) = 255.36787 = 255.268
255.268 tons of sand are added to the beach over the 3-hour period
