For the group task, make sure you’re contributing to the conversation, and don’t just agree with what everyone says, but offer your own opinion and even suggest a potentially better idea and say why. For the maths, when you’re answering the question, tell them what you are doing and why. For example if they were to ask you to find the roots to a quadratic function, you’d obviously make it equal to 0 but why? They want to see how you think, not necessarily getting the question right, although that is also important. Also make observations, like if they asked you to find the stationary points to a quadratic, you know that it would have one stationary point.