Once the cake is removed from the oven, it has been exposed to the room temperature of 70°F. After 10 minutes, the cake's temperature decreased to 200°F, which is 150°F cooler than it initially was (350°F). As for the what is asked, 90°F is 260°F cooler than its original temperature (350°F).
This problem can be expressed in a ratio:
10mins:150<span>°F = N:260</span><span>°F
where N is how long it will take for</span><span> cake to cool to 90°F
</span>150<span>°FxN=10x260
</span>150N=2600
N=2600/150
N=17.33
N<span>≈20 minutes
Thus, it takes approximately 20 minutes </span><span>for the cake to cool to 90°F</span>
all u do is see what looked right and add
This follows from the half-angle identity for cosine.
Answer:
The sample size is 1875.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
The margin of error is:

Sampling error of 0.03.
This means that 
99.74% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
25% of all adults had used the Internet for such a purpose
This means that 
What is the sample size
The sample size is n. So



Simplifying by 0.03 both sides



The sample size is 1875.
The answer is 113 hope that helps