The area of a triangle whose sides are a, b and c is ________

(a)

\(\sqrt { \left( s-a \right) \left( s-b \right) \left( s-c \right) } \)sq. units

(b)

\(\sqrt { s\left( s-a \right) \left( s-b \right) \left( s-c \right) } \)sq. units

(c)

\(\sqrt { s\left( s\times a \right) \left( s\times b \right) \left( s\times c \right) } \)sq. units

(d)

\(\sqrt { s\left( s-a \right) \left( s-b \right) \left( s-c \right) } \) sq. units

The semi-perimeter of a triangle having sides 15 cm, 20 cm and 25 cm is _______.

(a)

60 cm

(b)

45 cm

(c)

30 cm

(d)

15 cm

If the sides of a triangle are 3 cm, 4 cm and 5 cm, then the area is _______.

(a)

3 cm²

(b)

6 cm²

(c)

9 cm²

(d)

12 cm²

The perimeter of an equilateral triangle is 30 cm. The area is _______.

(a)

\(10\sqrt { 3 } \) cm²

(b)

\(12\sqrt { 3 } \) cm²

(c)

\(15\sqrt { 3 } \) cm²

(d)

\(25\sqrt { 3 } \) cm ²

The total surface area of a cuboid is ______________

(a)

4a² sq. units

(b)

6a² sq. units

(c)

2(l + b)h sq. units

(d)

2(lb + bh + lh) sq. units