100 points please solve fast! Brainliest please!

Answer:
Step-by-step explanation:
The number of rectangles and combinations:
Total
Now the number of,
Rectangles and combinations are,
→ 1 rectangle = 6
→ 2 rectangles = 5
→ 3 rectangles = 4
→ 4 rectangles = 3
→ 5 rectangles = 2
→ 6 rectangles = 1
Then the total number is,
→ 6+5+4 + 3+2+1
→ 15 + 6 = 21
Hence, total number is 21.