Compare the areas and perimeters of shape A and shape B.

From previous calculations:
The area of shape A is $84\, \text{cm}^2$.
The area of shape B is $144\, \text{cm}^2$.
Comparing these values, $144\, \text{cm}^2 > 84\, \text{cm}^2$.
Therefore, the area of shape B is greater than the area of shape A.

From previous calculations:
The perimeter of shape A is $48\, \text{cm}$.
The perimeter of shape B is $24\, \text{cm}$.
Comparing these values, $48\, \text{cm} > 24\, \text{cm}$.
Therefore, the perimeter of shape A is greater than the perimeter of shape B.

Comparison of Areas:
The area of shape A is $\boxed{\text{84 cm}^2}$.
The area of shape B is $\boxed{\text{144 cm}^2}$.
Shape B has a larger area than shape A.

Comparison of Perimeters:
The perimeter of shape A is $\boxed{\text{48 cm}}$.
The perimeter of shape B is $\boxed{\text{24 cm}}$.
Shape A has a larger perimeter than shape B.