Vitamin K is primarily produced by bacteria in the gut microbiome of humans and other animals. Additionally, green leafy vegetables, such as spinach and kale, are rich sources of dietary vitamin K, specifically vitamin K1 (phylloquinone). Vitamin K2 (menaquinone) is found in fermented foods and animal products. Overall, both microbial synthesis and dietary intake contribute to the body's vitamin K levels.
Greens
There is no such thing as vitiman k
Vitiman C Vitiman C
Peas and bananas are both rich in Vitamin K, as are dark green leafy vegetables. Vitamin K aids in clotting, so people on 'blood-thinners' must be careful of their intake of these foods.
No, it is a metallic element.
Vitiman A is good for you
You can get a vitiman that is called garlic
Vitamin B1
vitiman c, of course!
Calcium
Yes, Keurig produces espresso K-Cups.
The fourier series relates the waveform of a periodic signal, in the time-domain, to its component sine/cosine frequency components in the frequency-domain. You can represent any periodic waverform as the infinite sum of sine waves. For instance, a square wave is the infinite sum of k * sin(k theta) / k, for all odd k, 1 to infinity. Using a Fourier Transformation, you take take a signal, convert it from time-domain to frequency-domain, apply some filtering or shifting, and convert it back to time-domain. Sometimes, this is easier than building an analog filter, even given that you need a digital signal processor to do it.