If the lens is convex image cannot be virtual
Multicellular organisms, as the name implies, have many types of cells, while unicellular organisms contain just one cell each. Both kinds of organisms reproduce through meiosis or mitosis. Multicellular organisms generally form the higher tiers in the web of life. These living beings, including plants and animals, have a more complex internal layout than unicellular creatures. They rely on specialized cells and cell departments for carrying out specific tasks, such as breaking down food, sending electrical messages and other duties necessary for supporting life. This distinction, called cell differentiation, lets multicellular organisms engage in more complex physical and cognitive tasks than unicellular organisms.In addition to having specialized cells, multicellular organisms have separate organ systems to perform specific tasks. These systems, such as the cardiovascular, digestive and respiratory systems, perform life processes necessary for survival. Digestive systems, for instance, deliver nutrients and energy to organs in the digestive tract, letting them process and digest food. These organ systems also facilitate communications between different types of systems, such as the circulatory and nervous systems.
<h2>About 1 trillion billion stars (21 0's)</h2><h2 />
There is an average of 100 billion stars per galaxy. But you are looking for a universe, which is bigger than a galaxy.
According to UCSB Science Line, there are about 1 trillion billion stars in the observable universe. That's one 1 and twenty-one 0's.