Answer: a. 19
Step-by-step explanation:
it only has 1 and itself
Yes, good job! Since AB and CD are congruent, so are the angles
Surface Area (SA) = Base Area (Ab) + Lateral Area (AL)
Base Area = 36cm^2
Lateral Face Area = 48cm^2
*If this is a quadrilateral pyramid, then it has 4 lateral faces, so just multiply the "one" lateral face by 4.
Lateral Area (AL) = 4 x Lateral Face Area
-> AL = 4 x 48 = 192 cm^2
So:
SA = Ab + AL
-> SA = 36 + 192
-> Surface Area = 228 cm^2
<h2><u>Given</u>:-</h2>
Let us assume the three angles to be angle 1, angle 2 and angle 3.
Angle 1 = 35°
Angle 2 = 120°
<h2><u>To</u> <u>find</u>:-</h2>
Angle 3.
<h2><u>Solution</u>:-</h2>

<h2><u>Step</u>-<u>by</u>-<u>step</u> <u>explanation</u>:-</h2>
We know that,

➪ ∠ 1 + ∠ 2 + ∠ 3 = 180°
➪ 35° + 120° + ∠ 3 = 180°
➪ 155° + ∠ 3 = 180°
➪ ∠ 3 = 180° - 155°
➪ ∠ 3 = 25°

<h2><u>To</u> <u>verify</u>:-</h2>
∠ 1 + ∠ 2 + ∠ 3 = 180°
✒ 35° + 120° + 25° = 180°
✒ 180° = 180°
✒ L. H. S. = R. H. S.

