A scientist wants to predict the next time there three comets will be at perihelion, the point in an object's orbit at which it is closest to the sun. Write one letter in each box to correctly complete the table. A. 2020
B. 2022
C. 2033
D. 2039

Comet name:
Encke
Wild 2
Crommelin

Semimajor axis of orbit (AU):
2.21
3.44
9.2

Last reached perihelion:
Mar-17
Jul-18
Aug-11

Next time it will reach perihelion:
(A, B, C, or D)
(A, B, C, or D)
(A, B, C, or D)

If football was tossed in air without gravity or friction the ball would go into space

An atom's smaller negative particles are at a distance from the central positive particles, so the negative particles are easier to move. 

Answer the above statement is ( false );

Distance covered = speed x timethe distance traveled going against the stream = distance traveled with the stream.therefore it is the speed and the time that are the variables.as he travels the same distance both ways, speed x time is the same for each way.going upstream his speed is 4 kph; going downstream his speed is 6 kph.therefore we have two simultaneous equations: time upstream x 4 = time downstream x 6time upstream + time downstream = 60 minutestherefore we have the equation: time upstream = 6/10 hour, time downstream therefore = 4/10 hour.distance traveled at 4km/hr in 6/10 hour = 24/10 = 2.4km.check: distance traveled at 6km/hr in 4/10 hour = 24/10 = 2.4km.