Which sentence expresses numbers correctly?

Which sentence expresses numbers correctly?
 A) Because the reception starts at five p.m., I will need to leave work early.
 B) Because the reception starts at 5 p.m., I will need to leave work early.
 C) Because the reception starts at 5:00 p.m., I will need to leave work early.

Ques. 2

Which of the following is an effective opening for a routine request message?
 A) Please answer the following questions about your Web services.
 B) My name is Jill Aubrey, and I am the office manager for Cape Consulting Inc.
 C) I recently read an article about your firm in the local newspaper.
 D) Cape Consulting Inc. is the premier communication-consulting firm in the Cape and islands area.

Ques. 3

Which sentence expresses numbers correctly?
 A) On January 3 we held the last planning meeting; on the 10th we implemented the plan.
 B) On January 3rd we held the last planning meeting; on the 10th we implemented the plan.
 C) On January third we held the last planning meeting; on the tenth we implemented the plan.

Ques. 4

When business writers request information or action that will likely be received positively, they should frontload their messages, which requires
 A) including an attachment.
 B) proofreading only the beginning of a letter.
 C) including a salutation or greeting.
 D) putting the most significant statement first.