Answer:
135.8 km² {option d}
Step-by-step explanation:
The given information is,
→ Height (h) = 9.7 km
→ Base (b) = 7 km
Formula we use,
→ 1/2 × b × h
The area of the face of triangle will be,
→ x = 1/2 × b × h
→ x = 1/2 × 7 × 9.7
→ x = 1/2 × 67.9
→ x = 67.9/2
→ [ x = 33.95 ]
The lateral area of the triangle will be,
→ 4 × x
→ 4 × 33.95
→ [ 135.8 km² ]
Hence, the lateral area is 135.8 km².
