Draw (or do whatever) 13 in tens and ones [1 ten block ,3 ones blocks] then draw 7 in ones. then show the breaking apart of the tens block then subtract it by 7.

8 0

3 years ago

The product of three consecutive prime numbers is 105. What is the sun of those three numbers?

MrRissso [65]

3*5*7=105
3+5+7=15
☺☺☺☺

8 0

4 years ago

Suppose a cold beer at 40°F is placed into a warm room at 70°F. Suppose 10 minutes later, the temperature of the beer is 48°F. U

Yuri [45]

Answer:

69.92°F

Step-by-step explanation:

Given:

Initial temperature ( i.e at time, t = 0) = 40°F

Temperature of the room = 70°F

Temperature after 10 minutes ( i.e at time t = 10 ) = 48°F

Now, from Newton's law of cooling

T'(t) = k(A - T(t))

T(t) temperature after time t

T'(t) = $\frac{\textup{dT}}{\textup{dt}}$

here, A is the room temperature

thus,

$\frac{\textup{dT}}{\textup{dt}}$ = k(70 - T)

$\frac{\textup{dT}}{\textup{70-T}}$ = kdt

on solving the differential equation, we get

T = $70-C^{-kt}$ ............(1)

Now from the boundary conditions,

i.e at time, t = 0; T = 40°F

we get,

40 = $70-C^{-k\times0}$

C = 30

and,

at time, t = 10; T = 48°F

thus,

48 = $70-30^{-k\times10}$

k = $\frac{\textup{-1}}{\textup{10}}ln\frac{11}{15}$

k = 0.03

Therefore,

for t = 25

from 1 we have

T = $70-30^{-0.03\times25}$

T = 70 - 0.0780

T = 69.92°F

3 0

3 years ago