Consider a relatively nearby, single star, that is, a star that is not a member of a binary system and has no known orbiting planets. listed below are a few properties of this star. classify each property as either something that we can observe or measure directly (with the aid of a telescope and instruments such as cameras or spectrographs) or something that we must infer indirectly (and hence is correct only if all of our assumptions are correct).
infer indirectly
a. color
b. parallax angle
c. spectral type
d. apparent brightness
e. luminosity
f. surface temperature
g. mass
h. radius

The earth remains in orbit around the sun due to the force of gravity. how does the force of gravity exerted by the sun on the earth compare to the force of gravity exerted by the earth on the sun?

I'm kinda lost ! 1. when marilyn takes her pet dog for a walk, the dog walks at a veryconsistent pace of 0.55 m/s. draw a position-time graph to representmarilyn's dog walking the 19.8 m distance from the front of her house tothe nearest fire hydrant.2. both car a and car bleave school when a stopwatch reads zero. car atravels at a constant 75 km/h, and car b travels at a constant 85 km/h. a) draw a position-time graph showing the motion of both cars. howfar are the two cars from school when the stopwatch reads 2 hrs? calculate the distances and show them on your graph. b) both cars passed a gas station 120 km from the school. when dideach car pass the gas station? calculate the times and show themon your graph.3. the figure below shows the position-time graph showing a shopper'smovement up and down the aisle at a store. a) write a story describing the shopper's movements at the store. b) when does the shopper have a position of 6 m? c) how much time passes between when the shopper enters the aisleand when he gets to a position of 12 m? what is the shopper's averagevelocity between 37 s and 46 s?

All the simple machines make work easier to do by changing the or of a force. a. size; type b. work; type c. size; direction d. type; direction