Questions

a -  at the peak of changes in blood pressure indicates the systiolic pressure.

IEEE 1284 is a standard that govern parallel communications.

• IEEE 1284 is a standard that defines bi-directional parallel communications between computers and other devices.

• It was originally developed in the 1970s by Centronics, and was widely known as the Centronics port, both before and after its IEEE standardization.

We know that, preceeded means to come before. 

Hence, the given sentence, preceded in death means that person had died before this person.

For example :: Rahul preceeded Ravi in death, means Rahul died before Ravi.

There are 60 minutes in an hour.

In ¾ of an hour there are (60 × ¾) minutes = 45 minutes.

In ¾ of an hour there are (60 × 45) seconds = 2700 seconds.

Siren sounds for every 5 seconds.

In 2700 seconds = 2700/5 = 540 times.

The count start after the first sound, the Siren will sound 541 times in ¾ of an hour.