Averaged over the summer months, even though there are more hours of daylight at the arctic circle (66 ½°) compared to at 40° latitude, there is a lower maximum daily temperature at the arctic circle (66 ½°) compared to at 40°. this is because (choose all correct statements):

a. at the arctic circle, the sun’s rays travel through a thicker layer of atmosphere, reducing the amount of solar energy reaching the ground.

b. the increased cloud cover at the arctic circle during the summer reduces the amount of solar energy reaching the ground.

c. at the arctic circle, solar energy reaching the ground is spread over a smaller area, reducing the intensity of solar energy reaching the ground.

d. at the arctic circle, the daytime position of the sun in the sky is lower (closer to the horizon), reducing the intensity of solar energy reaching the ground.