Area of the middle rectangular section = length x width = 35 x 20 = 700 square cm.
The radius of the circular sections is 25 cm
Area of a full circle is pi x r^2 = 3.14 x 25^2 = 1962.5 square cm.
There are two quarter circles which is 1/2 of a circle. The area of those would be 1962.5/2 = 981.25 square cm.
Total area of the figure = 700 + 981.25 = 1681.25 square cm
We want to know when we brought it back in to the room. at that time
the temperature difference is 80 - 42 = 38 so we have to solve
<span>
38=9<span>e<span>^−.3344t</span></span></span> for t
this time we get
<span><span>38 / 9</span>=<span>e^<span>−.3344t</span></span></span>
<span>t=<span><span>ln(<span>38 / 9</span>)</span><span> / −.3344</span></span></span>
<span>t=−4.3</span>
so 4.3 minutes before 2:10
Answer:
C. 9.5
Step-by-step explanation:
The Pythagorean Theorem: a^2 + b^2 = c^2.
4^2 + 8.6^2 = c^2
16 + 73.96 = c^2
c^2 = 89.96
c = 9.4847....
2.8 = 2 + 0.8
*let's analyze the decimal 0.8 as a fraction
0.8 = 8/10
*but if we divide the numerator and denominator by the same common factor of 2, we find that the fraction can be reduced to:
(8/2)/(10/2) = (4)/(5) = 4/5
*now evaluating the whole value of 2 (from the 2.8), we know there are a total of (5) - fifths in order to make a whole, so for 2 whole, we require:
2*(5/5) = (2*5)/5 = 10/5
*Now we add the fractions together:
2 = 10/5
0.8 = 4/5
10/5 + 4/5
*add numerators only, the denominator stays as a 5
(10 + 4)/5 = 14/5
*there are no common factors between 14 & 5 (other than 1, but that won't help reduce the fraction any), so the fraction is in it's simplest form:
answer is: 14/5