NO. It is illegal to mail ammunition in the US mail. It can be shipped by UPS or FedEx GROUND, but not by mail.
sent mail is e-mail you have sent to other e-mail addresses
You cannot. Once mail is sent it is sent.
The correct phrase is "mail you had sent earlier." "Sent" is the past participle form of the verb, and it is used with forms of "have" when forming the past perfect tense.
YES
Yes and no. Ammunition may not be shipped by US mail (exceptions for some extremely remote areas) but can be shipped by UPS or FedEx.
they sent troops, supplies, and ammunition. They also sent tanks and planes
Maybe. At least one major on-line seller of ammunition will not ship to Maryland.
If you sent it normal mail then you cannot trace it.
Domestic mail is sent to an received from the same country. Mail sent from Los Angeles to New York is an example.
It is illegal to open mail that is not addressed to you, even if it is sent to your address.
No, it is not legal to open someone else's mail that was sent to your address.
Yes, the Tower Loan checks have been sent out in the mail.