What is the proper way to augment the size (up to newsize) of an already allocated pointer ptr?

What are all the proper ways to initialize a variable a of the following type:

struct some_type {
    size_t s;
    double tab[3];
};

Penalty for wrong ticks.

What is the proper way to read an array of n double from a binary file myfile into

Assume count is already declared and has the proper type.

Consider a packet, temporarily stored in a queue of a store-and-forward packet switch, waiting to be transmitted over an outgoing link. Which of the following affect(s) the queuing delay experienced by this packet? 

(Many answers may apply.)

Which of the following operations may the network-layer of a device perform? 

(Many answers may apply.)

Which of the following are examples where a system relies on statistical multiplexing but it does not work due to user correlation?

(Many answers may apply.)

You are continuously and forever downloading an infinite amount of data from a video server onto your home computer. Your home has a 10 Gbps Internet connection. However, your average throughput is 1 Gbps (so, significantly smaller than what you might expect). What might be the reason? 

(Many answers may apply.)

Source S is connected to destination D over a single link of transmission rate R. S sends a single tiny little packet to D and nothing else. You expect the average throughput achieved by this communication to be:

What does a process do when it wants to send data over the Internet?

(Many answers may apply.)

Source S sends packet P1, then packet P2 to destination D. The two packets traverse the same path (the same sequence of links and network devices). There is no other traffic on the Internet. P1 takes significantly longer than P2 to arrive. Which is the dominant delay component for packet P1?