Answer:
I think it is difficult to determine what has caused climate change in the distant past because it must have been a long time ago so geologists can't carry out different experiments and figure out what gases the planet had conjured, so geologists can only make predictions based off the evidence they currently have from what the planet looked like before. The planet must have changed over the years, therefore the climate has also changed in the future, so they cannot work with how the planet looked in the past.
Answer:
Distance of the point where electric filed is 2.45 N/C is 1.06 m
Explanation:
We have given charge per unit length, that is liner charge density 
Electric field E = 2.45 N/C
We have to find the distance at which electric field is 2.45 N/C
We know that electric field due to linear charge is equal to
, here
is linear charge density and r is distance of the point where we have to find the electric field
So 
r = 1.06 m
So distance of the point where electric filed is 2.45 N/C is 1.06 m
Since U=0,
h=1/2gt^2 (h= ut+1/2gt^2, U=0)
h=1/2*10*4*4
h=80m
Greenhouse gases trap thermal energy and reflect the sun’s harmful radiation back to Earth is the answer
im not 100% sure tho
hope it helps:))