<span>What you need to do while answering this questions, is ask yourself what has cells - only if a thing has cells can you see those cells under a microscope. Objects of animal and plant origin have cells, so blood, plant and cork (made of tree bark) can have cells, and a box too, if it's made of wood. So we can''t exclude any answers based on this. We must then know the story of Robert Hook - and it was in fact a cork. He did this discovery around 1655. At the time his main interest was the microscope rather than the cork, and he used to cork to demonstrate the function of the microscope. The correct answer is CORK.</span>
Answer:
The ratio of their orbital speeds are 5:4.
Explanation:
Given that,
Mass of A = 5 m
Mass of B = 7 m
Radius of A = 4 r
Radius of B = 7 r
The orbital speed of satellite A,
......(I)
The orbital speed of satellite B,
......(I)
We need to calculate the ratio of their orbital speeds
Using equation (I) and (II)

Put the value into the formula


Hence, The ratio of their orbital speeds are 5:4.
Answer:
E1 = 2996.667N/C E2 = 11237.5N/C
Explanation:
E1 = kQ1/r^2
=8.99 x 10^9 x 30 x 10^-9/(30x10^-2)^2
= 2996.667N/C
E2 = kQ2/r^2
= 8.99 x 10^9 x 50 x 10^-9/(20x10^-2)^2
= 11237.5N/C
The direction are towards the point a
Answer:
X: Always attractive
Y: Infinite range
Z: Attractive or repulsive
ANSWER IS C