Correct Answer: B. Executive

Correct Answer: D. for lack of proof

Correct Answer: C. 15

Explanation

f(x) = x\(^3\) + px + q

f(3) 3\(^2\) + 3pf + q = 6

f\(^{1}\)(x) = 2x + p

f\(^1\)(3) = 2(3) + p = 0

p = -6

from 9 + 3p + q = 6

9 + 3(-6) + q = 6

9 - 18 + q = 6

-9 + q = 6

Q = 6 + 9

= 15

Correct Answer: B. was invented

Explanation

The correct answer is B. was invented.

Here's why:

1. Passive Voice: The telephone didn't invent itself; it *was invented* by someone. So, we need a passive construction.

2. Past Tense: The invention happened in the nineteenth century, which is a completed action in the past.

3. Simple Past: Was invented (Simple Past Passive) is used to describe a completed action that occurred at a specific time or period in the past.

Let's look at why the others are incorrect:

• A. had been invented: This is Past Perfect Passive. It's used for an action that happened *before another past action*. There's only one past action mentioned here (the invention), so Past Perfect isn't necessary.

• C. would have been invented: This is a conditional perfect passive, used for hypothetical situations in the past (something that *would have happened* if conditions were different). The sentence states a fact.

• D. was being invented: This is Past Continuous Passive. It describes an action that was *in progress* at a specific time in the past. While the invention process took time, the sentence is referring to the completed act of invention, not the ongoing process itself. Was invented states the historical fact of its completion.

Correct Answer: C. convenience

Correct Answer: D. the federal government

Explanation

(a) LASER - Light Amplification by Stimulated Emission of Radiation.

(b) A laser is a device that generates an intense beam of coherent monochromatic light.

Correct Answer: A. salty water

Correct Answer: B. Forces of demand and supply

Correct Answer: B) locomotion

Explanation

protection D) excretion Related Lesson: Human Locomotion | Animal Systems The correct answer is B. Explanation: Paramecium is a type of unicellular organism that has tiny hair-like structures called cilia on its surface. These cilia are used for various functions, such as movement, feeding, and sensing the environment. In this question, we are asked to identify the primary function of the cilia in paramecium. Option A suggests that the cilia are used for respiration, which is not correct. Paramecium obtains oxygen through its cell membrane and does not have specialized respiratory structures. Option B, which is the correct answer, suggests that the cilia are used for locomotion. This is true as the cilia beat in a coordinated manner to propel the organism through its environment. Option C suggests that the cilia are used for protection, which is not correct. Paramecium has other structures for defense, such as trichocysts, which are specialized organelles that can discharge a protective substance. Option D suggests that the cilia are used for excretion, which is not correct. Paramecium excretes waste through specialized structures called contractile vacuoles. Therefore, the correct answer is Option B, which states that the cilia in paramecium are used for locomotion.