Official street signs have a normed height of 84mm. What's the farthest distance to read such a sign? Is it the same whether you see the street sign in bright sunlight or at night?

A rectangular airstrip measures 32.30 m by 210 m, with thewidth measured more accurately than the length. Find thearea, taking into account significant figures.

Can you help with the second one. I have done the math several times and I always end up with 7.44. It's close to 7.44 (within ten per the guidance of the question.)  It is not 82 degrees.

To estimate the size of the moon, a person holds a round pencil of diameter 0.70 cm. When the pencil is 77 cm in front of his eye, the moon is completely covered by the pencil. (a) What is the angle subtended by the moon? (b) what is the diameter of the moon if it is 3.8x 108 m above the Earth surface? (a) 0.52 x x 10-3 rad; (b) [ 3.54 x 106 m.

In aviation, it is helpful for pilots to know the cloud ceiling, which is the distance between the ground and lowest cloud. The simplest way to measure this is by using a spotlight to shine a beam of light up at the clouds and measuring the angle between the ground and where the beam hits the clouds. If the spotlight on the ground is 0.75 km from the hangar door as shown in the image below, what is the cloud ceiling? 20° 0.75 km

The speed of light to five significant figures is 2.9979 * 108m>s.What is the speed of light to three significant figures?

ER, d. = ER, d. Where: ER1 = 30mR/hr || ER2 5mR/hr d1 3 inches d2 0. inches ||

A hot air balloons gondola is suspended below a cloth envelope containing 2.775 x 10^8 liters of hot air. How many milliliter's of hot air is this?