images = new Array(7);

images[0] = "<img src='../images/employees/Employee1.png'>";
images[1] = "<img src='../images/employees/Employee2.png'>";
images[2] = "<img src='../images/employees/Employee3.png'>";
images[3] = "<img src='../images/employees/Employee4.png'>";
images[4] = "<img src='../images/employees/Employee5.png'>";
images[5] = "<img src='../images/employees/Employee6.png'>";
images[6] = "<img src='../images/employees/Employee7.png'>";

index = Math.floor(Math.random() * images.length);

document.write(images[index]);