Answer:
1) The angle would be 150 degrees
a) coordinates would be (
,
)
b) Trigonometric ratios:
sin: 
cos:
tan: 
csc: 2,
sec:
cot: 
Explanation:
simplifys to
which has a reference angle of
. We can take the coordinates of
and make the x value negative to find the correct coordiantes. Then, using those coordinates, plug the into the trigonomic equations.
For example, sin in opposite/hypotenuse. So sin = 1/2 divided by 1. Then you can find the rest of the equations that way.
cos= adjacent/hypotenuse
tan= sin/cos
csc= hypotenuse/opposite
sec= hypotenuse/adjacent
cot= cos/sin
What the data means about the amount of money people spend on purchasing accessories for the their mobile phones is that;
on the average, people spend between 43 and 57 dollars on every accessory they buy.
<h3>Confidence Interval</h3>
We are told that;
Mean is $50
Standard deviation from the mean is $7
From the empirical rule, since standard deviation from the mean is $7, then we can conclude that the confidence interval is;
CI = 50 ± 7
CI = (50 - 7), (50 + 7)
CI = (43, 57)
In conclusion, this means that on the average, people spend between 43 and 57 dollars on every accessory they buy.
Read more about Confidence interval at; brainly.com/question/17097944
By using a woodstove, the kilograms of wood required to
heat a room to 20°C is 3 kg
<h3>Efficiency of a machine</h3>
- Efficiency is the percent of work put into a machine (input work) to that of the work done by the machine (output work).
- Efficiency of a machine is always less than 100% because the output work is always less than the input work because some of the input work is used to overcome friction.
Efficiency = work output/work input * 100%
Efficiency of fireplaces = 15%
Amount of food required to heat a room to 20°C = 15 kg
Assuming efficiency of 100%, amount of wood required will be X kg:
X = 15% * 15 kg
X = 2.25 Kg
By switching to woodstoves which are 75% efficient, amount of wood required will be Y kg:
Y = 2.25 kg / 75%
Y = 3 kg
Therefore, by using a woodstove, the kilograms of wood required to
heat a room to 20°C is 3 kg
Learn more about efficiency of machines at: brainly.com/question/3617034