4 significant figures.
we can start counting the numbers after all the zeros in front. the zeros in front doesn't count in. but the zeros after the first number that is 1 or larger counts.
therefore we only need to look at 3010
The distance of the ball from the foot of the tower is : 35.18m
The ball would be moved 57.2m away from the foot of the tower for the Angle of elevation to be halved.
<h3>What is angle of elevation?</h3>
Angle of elevation is the angle formed between the horizontal and the line of view from the vertical.
Analysis:
The height of the tower and the distance of the ball from the foot of the tower form a right angle triangle.
so we use trigonometry.
a) let distance of the ball from foot of tower be x.
so that, tan 52 = 45/x
x = 45/tan52
x = 45/1.279 = 35.18m
b) let the distance of the ball in the new position from the foot of the tower be y.
if the angle of elevation is halved, then new angle is 52/2 = 26°
tan 26 = 45/y
y = 45/tan26 = 45/0.487 = 92.4m
distance moved from old position to new position = 92.4 - 35.18 = 57.2m
In conclusion, the distance of the ball from the foot of the tower and the distance the ball should move to make its elevation 26° are 35.18m and 57.2m respectively.
Learn more about angle of elevation: brainly.com/question/88158
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From the cars parked in the lot he will earn (40)($10)=$400, but he will need to pay $50 for the rent. Thus his total $ earned will be $400-$50=$350.
Answer:
160 visitors.
Step-by-step explanation:
Given:
An average of 145 people visited a 4-day exhibition on the first 3 days, <u>means here average people visited in 3 days is given 145.</u>
Average = 145
Number of people, n = 3
Another 205 people visited the exhibition on the fourth day.
To find:
What is the average number of visitors per day ?
Solution:
<u>First of all we will find total number of people visited in 3 days:-</u>
As we know:


Multiplying both sides by 3

Thus, we found that total number of people visited in 3 days is 435 and as 205 people visited in fourth day, then total number of people increased to
435 + 205 = 640
Now, sum of total observations( total number of people ) = 640
And number of observation ( number of days ) = 4
Now, we will calculate average number of visitors visit per day :-


Thus, the average number of visitors per day is 160 visitors.
I’m pretty sure it’s the third one sorry if i’m wrong