Answer:

Explanation:
The area of a telescope lens is 6.668 × 10³ mm²
We need to convert the area in ft².
We know that,

It means,

or

So, the required answer is
.
Answer:
The resonance structure for the cyclopentadienyl anion is shown in the drawing below.
Explanation:
The resonance representation of the cyclopentadienyl anion shows that it is a stable ion. On the other hand it is important to note that it has 6 π electrons and is aromatic.
Answer:
HNO2
Explanation:
Because H2CO3 is a weak acid in CH3COOH