Answer:
your answer is the 2nd one
Step-by-step explanation:
Answer:
Sin, Cos, Tan and others are used to calculate the ratios of the sides of a right angled triangle by taking a certain angle as the angle of reference.
On the other hand, Sin‐¹, Cos‐¹ and Tan-¹ are used to find the reference angle used to calculate the ratio of sides.
For this question,
we need to find which option should used to calculate the angle the slide makes with the vertical support.
So the option will have to be either A, C or E.
here, the base is 2.81m and hypotenuse is 3.64m.
we know, Cos = base / hypotenuse
So the angle is given by Cos-¹(2.81/3.64)
Option C
Answer:

Step-by-step explanation:
<u>Surface Areas
</u>
Is the sum of all the lateral areas of a given solid. We need to compute the total surface area of the given prism. It has 5 sides, two of them are equal (top and bottom areas) and the rest are rectangles.
Computing the top and bottom areas. They form a right triangle whose legs are 4.5 mm and 6 mm. The area of both triangles is

The front area is a rectangle of dimensions 7.7 mm and 9 mm, thus

The back left area is another rectangle of 4.5 mm by 9 mm

Finally, the back right area is a rectangle of 6 mm by 9 mm

Thus, the total surface area of the prism is


To find the contribution of each man (this is a sexist problem as women could work as well, but that’s besides the point) take 5/2 and then multiply that value by 20 and you’ll find it takes 50 hours for two men to do it.
Answer: 50 hours